Remote Communications - GE MOV 2000 Instructions Manual

2. OPERATION PRINCIPLES

2.6. REMOTE COMMUNICATIONS

The relay has 2 serial gates and three connectors. Gate 1 can be reached from the front of the relay in connector
1 (PORT 1 connector) or from the back (PORT 2 connector). The second gate can be reached from connector 3
(PORT 3 connector) which is located on the rear.
There are different models each with a different physical connection for the PORT 3 connector (RS-232 or fibre-
optic). In the "RS232" models the three connectors are RS232. In the "RS232 and fibre-optic" models the PORT1
and PORT2 connectors are RS232 while the PORT3 connector is replaced by a fibre-optic connector.
The PORT 1 connector has priority over the PORT 2 connector and is selected when the DCD (Data Carrier
Detect) signal is activated. Figure 8 shows how to make the connections to a personal computer.
Gate 1 (PORT 1 and PORT 2 connectors) and 2 (PORT 3 connector) are independent and the unit can
serve them simultaneously.
The communications protocol is the same as that used for the rest of the GE digital protection systems and
requires the use of the GE-LOCAL software. The instruction book for this program, which facilitates dialogue with
the relay, is supplied with the unit. The protocol is reliable and allows communication with different protection
systems. It guarantees very efficient data transfer (especially for the oscillography and other large files) along with
error detection and automatic communication recovery.
The status of the local/remote communication is indicated on the front of the unit by LED indicator 16 (the
last LED in the right-hand column.) Local communication refers to communication via the keyboard/display (local
display showing any information except for the initial MOV GENERAL ELECTRIC screen), or via communications
gate 1 (PORT 1, PORT2 connectors), and remote communication refers to connection via gate 2 (PORT 3 rear
connector).
Local and remote communications can exist at the same time, although there is only one possibility for
changing settings and carrying out operations, since this can only be done with the communication which has
priority (local communication) while the other is limited only to accessing information. When the local
communication is interrupted, either by the disconnection of PORT 1 connector or because the HMI is on the initial
screen (a situation which can be caused intentionally, or automatically if no key has been pressed for 15 minutes),
the remote communication recovers the ability to modify settings and carry out operations.
16 MIV Digital Multifunctional Protective Relay GEK-106271